LiquidTWI: High-performance LCD library for I2C Backpack Module

Breakout boards, sensors, other Adafruit kits, etc.

Moderators: adafruit_support_bill, adafruit

Please be positive and constructive with your questions and comments.
User avatar
1rj
 
Posts: 6
Joined: Sat Sep 17, 2011 5:39 pm

Re: LiquidTWI: High-performance LCD library for I2C Backpack Module

Post by 1rj »

PS: I did want to thank you for pointing out the potentiometer on the backpack. I didn't realize that it was there but now do. Although I could see the blocks very well. After I decide what to do with the arduino - I will definitely test the backpack potentiometer if I have a problem. Thanks again.

User avatar
1rj
 
Posts: 6
Joined: Sat Sep 17, 2011 5:39 pm

Re: LiquidTWI: High-performance LCD library for I2C Backpack Module

Post by 1rj »

IMG_5490.jpg
IMG_5490.jpg (58.17 KiB) Viewed 4275 times
I'm using the "Hello World" I2C (not the TWI) and verified the slave address of the backpack and changed the LCD display info to reflect my 20x4 LCD: "4, 20". I haven't ever seen "Hello World" since trying to start the I2c.
Attachments
IMG_5489.jpg
IMG_5489.jpg (51.26 KiB) Viewed 4275 times

User avatar
1rj
 
Posts: 6
Joined: Sat Sep 17, 2011 5:39 pm

Re: LiquidTWI: High-performance LCD library for I2C Backpack Module

Post by 1rj »

The arduino micro-controller is now working and flashing lights as it should be. I posted the pics to see if if anyone can help - thanks

fmalpartida
 
Posts: 2
Joined: Wed Dec 07, 2011 4:15 pm

Re: LiquidTWI: High-performance LCD library for I2C Backpack Module

Post by fmalpartida »

I see that that board is a bit different from that distributed by adafruit.

If that board uses the PCF8574 ASIC, give the New LiquidCristal library a shot. You can download it from: https://bitbucket.org/fmalpartida/new-l ... /wiki/Home

Also check that the I2C SCL and SCK are not swapped around.

Hope it helps.

User avatar
engineer
 
Posts: 5
Joined: Thu Sep 15, 2011 11:59 am

Re: LiquidTWI: High-performance LCD library for I2C Backpack Module

Post by engineer »

Just a shot here... try untwisting the all of the wires, especially the data and clock wires between the arduino and the lcd backpack. You may be getting some crosstalk between the two signals...

User avatar
bghobby
 
Posts: 5
Joined: Tue Feb 22, 2011 11:10 pm

Re: LiquidTWI: High-performance LCD library for I2C Backpack Module

Post by bghobby »

It appears that the library will no longer compile under Arduino 1.0. I believe the problem to be that the read(), print() and write() methods in the Stream class have been changed to return a variable of type "size_t" whereas previously these returned a "void". I would assume that the classes used in this library that have these methods are all subclasses of Stream and therefore a definition needs to be changed somewhere, perhaps in the .h file (although I don't have time right now to look through the library source code). If I understand this correctly (from the Arduino 1.0 release notes, that is), then the actual code that uses these methods will not change, since there was never a presumption of a return value. However, the C++ compiler seems to complain when it thinks you are trying to override a method that returned a value with one that returns a void.

I would like to request that the developer of this EXCELLENT library please update it for Arduino 1.0. My application could not tolerate the slowness of the Adafruit LCD-I2C library; this library is more than 10x faster and quite necessary in my application where the Arduino must read various inputs at least every few milliseconds.

Thanks.

User avatar
1rj
 
Posts: 6
Joined: Sat Sep 17, 2011 5:39 pm

Re: LiquidTWI: High-performance LCD library for I2C Backpack Module

Post by 1rj »

Hi - Had hand surgery so unable to get back here till now. I've started all over with everything again. I think the problem could be the jumper in the backpack. The data sheet says that it comes set for serial rather than i2c. I'm having trouble finding it and the data sheet doesn't say or show where it is. I have the i2c serial backpack from web4robot.com 4x20 LCD from adafruit. Here is a link to the data sheet which shows a picture of the backpack if anyone might help. http://web4robot.com/files/SerialLCDCtrl.pdf. Thanks again for you help. I'm following all the suggestions but still no luck.

adafruit
 
Posts: 12151
Joined: Thu Apr 06, 2006 4:21 pm

Re: LiquidTWI: High-performance LCD library for I2C Backpack Module

Post by adafruit »

1RJ wrote:Hi - Had hand surgery so unable to get back here till now. I've started all over with everything again. I think the problem could be the jumper in the backpack. The data sheet says that it comes set for serial rather than i2c. I'm having trouble finding it and the data sheet doesn't say or show where it is. I have the i2c serial backpack from web4robot.com 4x20 LCD from adafruit. Here is a link to the data sheet which shows a picture of the backpack if anyone might help. http://web4robot.com/files/SerialLCDCtrl.pdf. Thanks again for you help. I'm following all the suggestions but still no luck.
hi there, to be clear, you're having difficulty using a product we dont sell use or support. for technical support for this product we suggest contacting the distributor. they'll have their own tech support forums! thanks :)

Mikemolang
 
Posts: 13
Joined: Sun Dec 26, 2010 5:38 pm

Re: LiquidTWI: High-performance LCD library for I2C Backpack Module

Post by Mikemolang »

Where can I download the library? I tried this link from the first post:

LiquidTWI library is attached to this post, also mirrored here: http://hostfile.org/LiquidTWI.rar

...without success. I could also not see it attached anywhere on the post.

FalconFour
 
Posts: 14
Joined: Sun Jun 12, 2011 9:49 am

Re: LiquidTWI: High-performance LCD library for I2C Backpack Module

Post by FalconFour »

Yeah... Hostfile died some months ago and notifications (from people like you) about what links I've posted around the 'net that are now dead are slowly trickling in. But like Hostfile, LiquidTWI is somewhat outdated too... several reports about it being incompatible with Arduino v1.0+ kinda made me bummed a bit. All my Arduino stuff is in a box I haven't touched in months... I'm kinda hoping someone else would pick up the torch and run with it. But I'll dig up the archived file and post it on my Dropbox where it'll stay active forever. Just a sec... I'll update the original post in a minute.

("we are unable to confirm that this post is not spam - please complete the captcha below"?! Are you for freakin' real?!)

FalconFour
 
Posts: 14
Joined: Sun Jun 12, 2011 9:49 am

Re: LiquidTWI: High-performance LCD library for I2C Backpack Module

Post by FalconFour »

Wait, how did you miss this??

Image

User avatar
lungstruck
 
Posts: 2
Joined: Thu Jan 24, 2013 11:46 pm

Re: LiquidTWI: High-performance LCD library for I2C Backpack Module

Post by lungstruck »

several reports about it being incompatible with Arduino v1.0+ kinda made me bummed a bit. All my Arduino stuff is in a box I haven't touched in months... I'm kinda hoping someone else would pick up the torch and run with it.
It appears someone did, forum user Stephanie posted an updated LiquidTWI in another thread. It's available here:

https://github.com/Stephanie-Maks/Arduino-LiquidTWI

I tested it under 1.0.3 and it work great. It also includes kch's patch which is a nice bonus.

dasaint80
 
Posts: 4
Joined: Wed May 15, 2013 12:54 pm

Re: LiquidTWI: High-performance LCD library for I2C Backpack Module

Post by dasaint80 »

either one doen't work on 1.0.5....

User avatar
lungstruck
 
Posts: 2
Joined: Thu Jan 24, 2013 11:46 pm

Re: LiquidTWI: High-performance LCD library for I2C Backpack Module

Post by lungstruck »

either one doen't work on 1.0.5....
What doesn't work? I just installed Arduino 1.0.5, added Stephanie Mak's updated LiquidTWI to my libraries and ran the included Hello World and PerfTest examples w/o any problem.

FalconFour
 
Posts: 14
Joined: Sun Jun 12, 2011 9:49 am

Re: LiquidTWI: High-performance LCD library for I2C Backpack Module

Post by FalconFour »

Hello again!

FINALLY dug out my i2c LCD board and played around with this thing. The compile errors were caused by two things: a name change in Wire (from send() to write()), and a format change for the write() function. In order for LiquidTWI's write() to work, it needs to mesh up with Print's write(), which now returns a size_t instead of nothing (void). A couple compiler problems, that's it. /facepalm

Also bug-fixed (maybe...) the occasional initialization glitch by increasing the start-up delay to 100ms. That's only done once, so it shouldn't affect performance at all.

Finally, this thing is ready for the latest Arduino IDE. Sorry it took so long... :oops:

See first post for updated version and information.

Locked
Please be positive and constructive with your questions and comments.

Return to “Other Products from Adafruit”